select ID,COMMAND,DESCRIPTION,CONTENT from message where 1=1 com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'COMMAN
select ID,COMMAND,DESCRIPTION,CONTENT from message where 1=1
com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'COMMAND ='??????'' at line 1
這是我的查詢語(yǔ)句，以及錯(cuò)誤報(bào)告，求指教
2017-06-01
這個(gè)是傳入到數(shù)據(jù)庫(kù)的時(shí)候沒(méi)有對(duì)數(shù)據(jù)進(jìn)行編碼，數(shù)據(jù)庫(kù)讀不到數(shù)據(jù)，jdbc:mysql://127.0.0.1:3306/micro_message?characterEncoding=utf8","root","root"
2016-07-27
是空格的問(wèn)題，?sql.append(" and COMMAND =?");
在and 的前面加一個(gè)空格。
2016-07-27
package com.imooc.servlet;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.imooc.bean.Message;
/*
?*列表頁(yè)面初始化控制?
?*/
@SuppressWarnings("serial")
public class ListServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
// TODO Auto-generated method stub
try {
req.setCharacterEncoding("UTF-8");
String command=req.getParameter("command");
String description=req.getParameter("description");
Class.forName("com.mysql.jdbc.Driver");
?Connection conn= DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/micro_message","root","admin");
?StringBuilder sql=new StringBuilder();
?sql.append("select ID,COMMAND,DESCRIPTION,CONTENT from message where 1=1");
List<String> paramlist=new ArrayList<String>();
?if(command!=null &&!"".equals(command.trim())){
?sql.append("and COMMAND =?");
?paramlist.add(command);
?}
?if(description!=null &&!"".equals(description.trim())){
?sql.append("and DESCRIPTION =?");
?paramlist.add(description);
?}
?PreparedStatement stat=conn.prepareStatement(sql.toString());
for (int i=0;i<paramlist.size();i++) {
stat.setString(i+1, paramlist.get(i));
}
ResultSet rs=stat.executeQuery();
List <Message> messagelist=new ArrayList<Message>();?
System.out.println(sql);
while(rs.next()){
Message message=new Message();
? ?message.setId(rs.getString("ID"));
? ?message.setCommand(rs.getString("COMMAND"));
? ?message.setDescription(rs.getString("DESCRIPTION"));;
? ?message.setContent(rs.getString("CONTENT"));
messagelist.add(message);
}
? ? ? ? ?req.setAttribute("messagelist", messagelist);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
req.getRequestDispatcher("/WEB-INF/jsp/back/list.jsp").forward(req, res);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(req, res);
}
}